Buxus plant named ‘RLH-BI’

ABSTRACT

A new and distinct cultivar of  Buxus  plant named ‘RLH-BI’, characterized by its compact, outwardly spreading to decumbent, billowy and mounding plant habit; vigorous growth habit; moderately rapid growth rate; freely branching habit; flexible lateral branches that are resistant to cracking and splitting; bright green-colored developing leaves that become dark green with development; and good winter hardiness.

Botanical designation: Buxus microphylla var. koreana.

Cultivar denomination: ‘RLH-BI’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Buxus plant, commercially referred to as Boxwood, botanically known as Buxus microphylla var. koreana and hereinafter referred to by the name ‘RLH-BI’.

The new Buxus plant is a naturally-occurring branch mutation of Buxus microphylla var. koreana ‘Kingsville’, not patented. The new Buxus plant was discovered and selected by the Inventors in 1991 on a single plant of ‘Kingsville’ in a controlled outdoor nursery environment in Long Creek, Oconee County, S.C.

Asexual reproduction of the new Buxus plant by semi-hardwood and hardwood cuttings in a controlled environment in Long Creek, Oconee County, S.C. since 1996 has shown that the unique features of this new Buxus plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Buxus have not been observed under all possible environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘RLH-BI’. These characteristics in combination distinguish ‘RLH-BI’ as a new and distinct Buxus plant:

-   -   1. Compact, outwardly spreading to decumbent, billowy and         mounding plant habit.     -   2. Vigorous growth habit and moderately rapid growth rate.     -   3. Freely branching habit; pruning is typically not required.     -   4. Flexible lateral branches that are resistant to cracking and         splitting (breaking) at the nodes.     -   5. Bright green-colored developing leaves becoming dark green         with development.     -   6. Good winter hardiness.     -   7. Resistant to Boxwood leaf miners, psyllids and mites.

Plants of the new Buxus differ primarily from plants of the parent, ‘Kingsville’, in the following characteristics:

-   -   1. Plants of the new Buxus are billowy and outwardly spreading         whereas plants of ‘Kingsville’ are dense and congested which         exacerbates susceptibility to pathogen and pest problems.     -   2. Plants of the new Buxus are faster growing than plants of         ‘Kingsville’.     -   3. Lateral branches of plants of the new Buxus are flexible and         resistant to cracking and splitting whereas lateral branches of         plants of ‘Kingsville’ are rigid and prone to cracking and         splitting at the nodes.

Plants of the new Buxus can be compared to plants of Buxus microphylla var. japonica ‘Morris Dwarf’, not patented. In side-by-side comparisons conducted in Seneca, S.C., plants of the new Buxus differed primarily from plants of ‘Morris Dwarf’ in the following characteristics:

-   -   1. Plants of the new Buxus were not as compact and globular as         plants of ‘Morris Dwarf’.     -   2. Plants of the new Buxus were billowy and outwardly spreading         whereas plants of ‘Morris Dwarf’ were dense and congested which         exacerbates susceptibility to pathogen and pest problems.     -   3. Plants of the new Buxus were more vigorous and grew faster         than plants of ‘Morris Dwarf’.     -   4. Lateral branches of plants of the new Buxus were flexible and         resistant to cracking and splitting whereas lateral branches of         plants of ‘Morris Dwarf’ were rigid and prone to cracking and         splitting at the nodes.     -   5. Plants of the new Buxus were more winter hardy than plants of         ‘Morris Dwarf’.

BRIEF DESCRIPTION OF THE PHOTOGRAPH

The accompanying colored photograph illustrates the overall appearance of the new Buxus plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photograph may differ slightly from the color values cited in the detailed botanical description which accurately describe the colors of the new Buxus plant.

The photograph comprises a side perspective view of a typical plant of ‘RLH-BI’ grown in an outdoor nursery.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photograph and following observations, measurements and values describe plants grown during the summer under partial and full sun conditions in an outdoor nursery in Seneca, S.C. During the production of the plants, day temperatures ranged from −5° C. to 45° C. and night temperatures ranged from −25° C. to 35° C. Plants were 16 years old when the photograph and description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2007 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Buxus microphylla var. koreana ‘RLH-BI’. -   Parentage: Naturally-occurring branch mutation of Buxus microphylla     var. koreana ‘Kingsville’, not patented. -   Propagation:     -   -   Type.—By semi-hardwood and hardwood cuttings.         -   Time to initiate roots, summer.—About 10 to 14 days at             27° C. to 30° C.         -   Time to initiate roots, winter.—About 18 to 25 days at             16° C. to 17° C.         -   Time to produce a rooted young plant, summer.—About 45 to 60             days at 27° C. to 30° C.         -   Time to produce a rooted young plant, winter.—About 60 to 80             days at 16° C. to 17° C.         -   Root description.—Medium in thickness to thick; fibrous,             coarse and cord-like; color, close to NN155C becoming closer             to 164D with development.         -   Rooting habit.—Freely branching; abundant, dense. -   Plant description:     -   -   Plant and growth habit.—Evergreen shrub with compact,             outwardly spreading to decumbent, billowy to mounding and             uniform plant habit; vigorous growth habit and moderately             rapid growth rate.         -   Branching habit.—Freely branching habit; bushy appearance;             typically two to five lateral branches develop each spring             and summer; pruning is typically not required.         -   Plant height.—About 60 cm.         -   Plant width (spread).—About 120 cm. -   Lateral branch description:     -   -   Length.—About 1.5 cm to 3.5 cm.         -   Diameter.—About 7 mm to 10 mm.         -   Internode length.—About 5 mm to 25 mm.         -   Strength.—Strong and flexible rending the plants resistant             to cracking and splitting (breaking) at the nodes.         -   Texture.—Smooth; glabrous.         -   Color, developing stems.—Close to 137D.         -   Color, developed stems.—Close to 199D. -   Leaf description:     -   -   Arrangement.—Opposite, simple.         -   Aspect.—Mostly upright.         -   Length.—About 1.2 cm to 2.6 cm.         -   Width.—About 4 mm to 12 mm.         -   Shape.—Obovate to oblanceolate.         -   Apex.—Obtuse or aristulate.         -   Base.—Attenuate.         -   Margin.—Entire.         -   Texture, upper surface.—Smooth; mostly glabrous, proximal             end of mid-vein, sparsely lanulose.         -   Texture, lower surface.—Coriaceous; glabrous.         -   Venation pattern.—Pinnate, reticulate.         -   Color.—Developing leaves, upper surface: Close to 138A.             Developing leaves, lower surface: Close to 139C. Fully             expanded leaves, upper surface: Close to 137A; venation,             close to 137A. Fully expanded leaves, lower surface: Close             to 144A; venation, close to 139D.         -   Petiole.—Length: About 1.2 mm to 1.5 mm. Diameter: About 0.4             mm to 1.1 mm. Texture, upper surface: Coriaceous; sparsely             pubescent. Texture, lower surface: Coriaceous; glabrous.             Color, upper surface: Close to 137A. Color, lower surface:             Close to 139D. -   Flower description: Flower initiation and development has not been     observed on plants of the new Buxus. -   Disease & pest resistance: Plants of the new Buxus have been     observed to be resistant to Boxwood leaf miners, psyllids and mites.     Additionally, the billowy and spreading plant habit of the new Buxus     lends to tolerance to pathogens common to Buxus plants. -   Landscape performance: Plant of the new Buxus have been observed to     have excellent landscape performance and to tolerate wind, rain and     temperatures ranging from about −25° C. to about 45° C. 

It is claimed:
 1. A new and distinct Buxus plant named ‘RLH-BI’ as illustrated and described. 